IDS Stainless Steel Aquarium CO2 Plant Atomizer Diffuser System with Bubble Counter for Plant Tank Built-in replaceable high-density ceramics, good refinement effect, washable replacement This applies only to the inner diameter of the atomizer and an inner diameter 12MM cartridge hose. Trachea interfaces with anti-lock off function to prevent high pressure detached Water interface with double pagoda-style interface design, easy to install and effective to prevent water loss Durable alloy casing, size is 12cm x 6.5cm x 2.5cm